On these web pages we
take a critical look at climate change and particularly climate change
over the last 25 years where data is good. Some of the material comes
from an old website
at erols.com that now no longer exists. Much of material will be new
based
on new developments in the last few years.

The material is
organized into
several categories, with introductory statements on this page and more
detail
discussion in the links. The material will be updated form time to time.

PROBLEMS WITH THE GREENHOUSE WARMING THEORY

There are several
problems with the theoretical underpinnings of the standard IPCC theory
of global warming
due to anthropogenic greenhouse gases (AGHG). These problems are listed
here
with more discussion in the links.

1. The IPCC theory has a
roughly 3.5 W/m2 decrease in outgoing thermal radiation from
a doubling of carbon dioxide. The number is based upon an instantaneous
doubling of carbon
dioxide and assumes no change in the continuum radiation. This topic is
discussed
further here.

2. The sensitivity of
climate without any feedbacks is (33 C / 148 W/m2) or 0.22
C/W/m2, so the basic change in climate is 0.22 * 3.5 C or
0.7 C for a doubling of carbon dioxide. Recently Schwartz has deduced
empirically that the climate sensitivity is approximately 0.25 C/W/m2,
and equilibrium time is 2-3 years (Requirements for empirical
determination of Earth's climate sensitivity by S. E. Schwartz at the
AAAS Annual Meeting, Denver CO, February 14-18, 2003

In contrast, the IPCC
says a doubling of carbon dioxide will cause a warming of 1.5 to 4.5 C
and have a climate sensitivity between 0.43 and 1.29 C/W/m2. They get these high
numbers by assuming a number of positive feedbacks exist including
changes in water vapor, cloud cover, and snow and ice cover. The water
vapor feedback is incorrect and is discussed here.

3. The sum total of all
feedbacks is assumed to be positive. Recent published work shows they
are negative and
these results are reviewed here.

4. IPCC economic models
overestimate the rate at which carbon dioxide will enter the atmosphere
over the next century.
It leads to farfetched warming numbers such as 5.8 C. A critique is
offered
here.

5. Some easily modeled
effects such as an increase in depolarization factor of air with more
carbon dioxide are totally neglected in the climate models. Further
discussion here.

Summary: Based upon the
first three points above, the upper limit on warming due to a doubling
of carbon dioxide is 0.7 C and it is probably much less. The high
numbers used by the IPCC are not supported by measurements.

ALTERNATIVE EXPLANATIONS FOR THE RECENT
WARMING

According to the surface
measurements, climate has warmed by about 0.18 C/decade since 1979.
Many people attribute all this warming to AGHGs, but alternative
explanations exist. They are listed below with links to further
discussion.

1. The sun may have
warmed over the last 25 years and caused most if not all the warming as
discussed here.

2. The albedo of the
Earth has decreased (the planet is getting darker and absorbing more
radiation). This will warm the planet and is discussed here. Land use changes are
also discussed here.

3. Contrails have
increased in recent years and will lead to a warming on regional and
perhaps a global scale as discussed here.

4. Fossil fuel burning
releases heat directly to the atmosphere and will cause a warming over
the continents. It is discussed here.

5. Urban heat islands
(UHI) are substantial (several degrees Celsius in many cases and larger
than the predicted AGHG warming). Placing thermometers near cities and
downwind of cities may lead to a warming that is falsely attributed to
AGHGs. The effect is substantial and is discussed here along with a mention of
land use changes. Further support that
urban heat islands represent half of the reported warming in the
twentieth century (0.3 C out of 0.6 C) comes by examining the changes
in the diurnal temperature range (DTR).

6. Other explanations
for the
recent warming include:

a. Decrease in explosive
volcanic eruptions in recent years.

b. Increased intensity
of El
Nino in the last few years.

c. More carbon aerosols
(soot) in the atmosphere.

d. Soot on snow.

e. Decreased
stratospheric ozone.

f. Internal changes in
circulation such as the Pacific Decadal Oscillation (PDO), North
Atlantic Oscillation (NAO), and Arctic Oscillation (AO).

CLIMATE MODEL VALIDATION SCORECARD

Starting in 1997, we
created a scorecard to see how climate model predictions were matching
observations. The picture is not pretty with most of the predictions
being wrong in magnitude and often in sign. An updated version of
the scorecard
can be found here. It may be updated yet
more depending upon the publicity that a claim receives or if readers
send suggestions.